Coolpix 5700 dead pixel?

it is a hot pixel. showing up in long shutter. you can enable NR in camera setting for such siturations, or send it back to nikon to get it "mapped" out, or see the "4500 has a raw mode" thread to check out the home made software to MAP the pixel out.

map it out means to tell the camera to replace the problematic pixel with nearby pixel. so you will never see it again.

of course doing such operation on your beloved camera with a beta/alphar home made software is a bit risky. you can always wait longer for it to stableize. good news is some people are already getting good result in this software already.
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Ka-Chun Cheng
Nikon 5K7
http://www.biblecrawler.com